The foam block is used to extend the snorkel on the cowl back to interface with the nose of the airbox. The foam is shaped to fill the gap then fiberglassed. Afterwards the foam is chipped out. As for the gasket, you can always make your own from stock gasket material.
Registration done, W&B done, Engine Run, working on AW paperwork!
PP SEL / A&P
I donate every year on my B-Day (in Dec)